You can set your watch by them, sure in the knowledge that a gaggle of Michelin tyre-like lumps will be stripping off their padded coats and trotting on to the field around the hour mark to lend their weight to the cause and ruining the game in the process.

If we all had a pound for every time that weary cliché is trotted out – “It’s no longer a 15-man game, it’s a 23-man game, it’s all about the bench, it’s all about the match-day squad” – we could retire tomorrow.

It is not a 23-man game. Rugby union is a 15-man game and many of us wish to the high heavens that it would revert to it.

Exeter were six tries to the good, leading 41-3 when the scourge appeared on the sidelines. You knew. You just knew it. The game would go to the dogs. And it did.

It lost shape, it lost meaning, it lost credibility. Yeah, yeah, the horrible mess was compounded by Exeter having two players sin-binned within a minute of each other. Of course that made a significant difference. But the process of disintegration had already begun. The Chiefs had made half a dozen substitutions by that point, only a couple of them injury enforced.

Fiddle and meddle – a coach has been given full rein to do just that, and very few can resist. Exeter head coach, Rob Baxter, even admitted as much afterwards. You can understand his logic.

The contest was as good as over and here was a chance to give backup players some precious game time out in the middle. All very sensible from his point of view.

And all very frustrating for those of us who brought up on an older truth – that 15 blokes go at it hammer and tongs for 80 minutes until the other lot wilt and that is when you get your reward.

What happened at Sandy Park? Cardiff were gifted a bonus point as they scored four tries, with a nod to the overflowing sin-bin as the prime reason for that.

What would we have paid to see Exeter continue to turn the screw, really ram home their advantage over the Blues, to carry on in that first-half vein? My gut feeling is that they would have posted at least 60 points, Cardiff would have been humiliated and that there would have been, at most, only one sin-binning.

One of the yellow cards was picked up by one of those replacements, Sireli Naqelevuki, within minutes of coming on to the field, for a reckless high tackle on Cardiff wing, Harry Robinson. It was in keeping with the mood of the moment: frantic, frenetic, unstructured as the new cast list tried to get used to each other.

All the poise had gone, that sense of a corps of blokes all perfectly tuned to each other’s radar, finding one another no matter how dense the traffic. Instead, it was fitful and terribly unfulfilling.

Players will never sound off about it. Coaches certainly will not do so as it extends their influence. But nobody can be truly satisfied with it. The players who get the shepherd’s hook from the sidelines feel aggrieved that they are not trusted to go the distance while the blokes on the bench sit there like stuffed dummies for most of the afternoon, their week’s preparation for the big moment dependent on the whim of a coach.

It used to be a matter of considerable pride for props to see their opposite number begin to weaken. What exactly is the reward for a dominant prop these days? Their opponents send on someone else to test him, fresh and raring to go. That cannot be right.

Of course, we know that health and safety will have their way, that front-rows must be protected, that substitutions are a welfare issue and that they are here to stay. That is as may be, although I would still favour trimming the replacement bench to a maximum of four players.

Rugby is a game of confrontation, of testing an opponent’s mental and physical resolve. May the stronger or more skilful man win. That is no longer the case. Beat one, here comes another. How long before we get specialist goal-kicking replacements? Rolling substitutions? It could never happen, you say? I wonder.

Let Sonny Bill be

Sonny Bill Williams, league, union, boxing, league, RWC2015 – whatever he touches turns to gold dust. Those who mock him for his butterfly tendencies, flitting from one sport to the other, have no joy in their soul.

Players do not bitch about him. SBW is a professional athlete, a hired hand. Commitment is a matter of contract these days, not heart.